The present invention is generally related to the field of internal combustion engines. In particular, the present invention relates to a barrel-type internal combustion engine capable of providing a power stroke from multiple cylinders simultaneously.
Engines come in many varieties and styles. For example, there are diesel, internal combustion, and external combustion engines, and within the internal combustion variety of engine there are several distinct types such as: V-type, In line-type, barrel-type internal combustion engines, and the like. Additionally, within the class of barrel-type engines are styles such as two stroke and four stroke engines.
Traditionally, all of these engine classes were only capable of providing a power stroke from one cylinder at a time. The general principle behind using engines to do work is to use the power stroke of the engine to turn a drive shaft which can be attached to any moving part intended to be moved by the engine. For example, the drive shaft can be attached to an axle and thereby turn wheels, can be attached to a propeller to turn the propeller, or can be used for any other suitable industrial or commercial use. The engine provides a torque force on the drive shaft that forces the shaft into motion. There are, however, several problems with this method of providing power from an engine.
The most significant problem is that the single firing provided by the explosion of combustible material during a power stroke causes vibrations within the engine and depending upon the attachment of the engine to a fixed device, the vibrations caused by the engine can cause the attachment of the engine to become loosened. Vibrational forces are amplified by the structural configuration of most engines resulting in the uneven balance of the engine. Further, vibrational forces have a tendency to reduce the longevity of the engine by vibrating the parts of the engine repeatedly and may provide a source of irritation to passengers of vehicles propelled by these engines.
Recently, barrel-type engines have been developed that can reduce the amount of vibrational forces act upon the engine. Generally, barrel-type engines have a set of cylinders on one end and a set of cylinders on the other end of the engine. The two sets of cylinders are arranged in-line with a piston that has a double head reciprocates within the in-line cylinders. The cylinders are arranged circularly around and parallel to the drive shaft. This arrangement provides a compact configuration and nearly perfect balance, resulting in reduced vibration.
The barrel-type engines fire a single cylinder on one end of the engine and during the duration of the power stroke a single cylinder from the other end is fired which reduces the vibration caused by the engine. However, the current configuration of these devices limits the amount of power and torque the engine is able to generate and does not completely balance the firing of the engine to further reduce the production of vibration from the engine.
The present invention addresses these needs, as well as other problems associated with existing barrel-type internal combustion engines.
The present invention is a barrel-type internal combustion engine. The engine is generally comprised of a plurality of cylinders arranged in in-line pairs, each in-line pair having a double headed piston therein. The cylinders are arranged surrounding a central shaft that has a cam thereon. The cam has two opposing sinusoidal surfaces extending outward and around the shaft for positioning the pistons in the cylinders and transferring the combustion energy to the output shaft. The cam has a plurality of alternating and equidistantly spaced rises and reverse rises forming each of the sinusoidal surfaces. The engine is constructed and arranged to align each rise and reverse rise with a cylinder such that the engine can produce a power stroke substantially simultaneously in each cylinder aligned with a rise and reverse rise.
The present device is designed to provide power strokes to multiple cylinders on each end of the engine that are arranged such that they are spaced equidistantly from each other around the drive shaft, thereby providing a balanced force around the shaft on each end of the engine, and have the sets of strokes of the two ends spatially offset from each other to provide lateral balance to the stroke forces.
One embodiment of the present invention is configured to provide two power strokes at one end of the engine that are in cylinders 180 degrees from each other and two strokes in cylinders 180 degrees from each other at the other end and wherein the two sets of strokes are offset by 90 degrees to each other. The configuration of the cylinders and the shape of the sinusoidal surfaces of the cam allows the four power strokes to take place substantially simultaneously on each power stroke of the engine.
One arrangement of the cylinders provides eight common cylinder chambers with double headed pistons defining eight cylinders on each end of the engine. A two-cycle engine with this arrangement allows the engine to provide thirty two power strokes per revolution of the drive shaft.
Another embodiment is configured to provide three power strokes at one end of the engine that are in cylinders 120 degrees from each other and three power strokes in cylinders 120 degrees from each other with an offset of 60 degrees between the sets of power stroke cylinders on the two ends. The configuration of the cylinders and the shape of the sinusoidal surfaces of the cam allows the six power strokes to take place substantially simultaneously on each power stroke of the engine. One arrangement of the cylinders of this configuration provides twelve common cylinder chambers with double headed pistons defining twelve cylinders on each end of the engine. A two-cycle engine with this arrangement allows the engine to provide seventy two power strokes per revolution of the drive shaft.
The formula that allows this system to provide power strokes to these multiple cylinders on every output shaft rotation provided that for each sinusoidal surface, the surface must have N rises (Nr) that are spaced at 360/Nr degrees from each other and N number of reverse rises(Nrr) spaced at 360/Nrr degrees from each other and positioned at an offset of 360/(Nr+Nr) degrees from one end of the engine to the other end. Furthermore, the amount of cylinders and their positioning must be equal to any number divisible by Nr+Nrr.
The aforementioned benefits and other benefits including specific features of the invention will become clear from the following description by reference to the accompanying drawings.